CRON(8) CRON(8)
NAME
cron - daemon to execute scheduled commands (Vixie Cron)
SYNOPSIS
cron
DESCRIPTIONCron should be started from /etc/rc or /etc/rc.local. It
will return immediately, so you don't need to start it
with '&'.
Cron searches /var/spool/cron for crontab files which are
named after accounts in /etc/passwd; crontabs found are
loaded into memory. Cron also searches for /etc/crontab
and the files in the /etc/cron.d/ directory, which are in
a different format (see crontab(5)).Cron then wakes up
every minute, examining all stored crontabs, checking each
command to see if it should be run in the current minute.
When executing commands, any output is mailed to the owner
of the crontab (or to the user named in the MAILTO envi-
ronment variable in the crontab, if such exists).
Additionally, cron checks each minute to see if its spool
directory's modtime (or the modtime on /etc/crontab) has
changed, and if it has, cron will then examine the modtime
on all crontabs and reload those which have changed. Thus
cron need not be restarted whenever a crontab file is mod-
ified. Note that the Crontab(1) command updates the mod-
time of the spool directory whenever it changes a crontab.
SEEALSO
crontab(1), crontab(5)
AUTHOR
Paul Vixie <paul@vix.com>
20 December 1993 1